Construction of a projection spectrograph and its use in optical spectroscopy classrooms demonstrations

This article describes a projection spectrograph for use in optical spectroscopy classrooms demonstrations. The apparatus is based on an overhead projector and permits the visualization of several phenomena such as, light dispersion by diffraction gratings, diffraction order, optical fluorescence, continuous and discrete optical emission spectra, and light absorption by liquids and solids. A historical survey about the optical spectroscopy development is also presented

Avaliação do florescimento de laranjeiras valência em condição de campo

Since citrus flowering is a key process in citriculture and its evaluation is often difficult due to the canopy structure and field sampling, the aim of this research was to give some directions regarding the evaluation of flowering in field-grown sweet orange plants. This study was conducted in a citrus orchard of sweet orange plants cv. 'Valencia' [Citrus sinensis (L.) Osbeck] grafted on 'Cleopatra' mandarin (Citrus reshni hort. ex Tanaka) or 'Rangpur' lime (Citrus limonia Osbeck) rootstocks, with North-South orientation. Generative structures [buds, flowers and fruitlets (diameter < 3 cm)] were quantified weekly between August and November 2005, by using a 1 m² frame positioned at the middle third of plant canopy, sampling a volume of about 1 m³. Frames were divided in two parts so that two people could take measurements, and were positioned at Southeast, Southwest, Northeast and Northwest orientations, using seven plants. The following flowering parameters were: (i) number of plants necessary for a representative evaluation of flowering; (ii) plant canopy position to be sampled, and (iii) volume to be evaluated. When considering practical aspects of crop production, a rapid, simple and representative method for flowering evaluation is necessary, especially for growers that frequently have to make strategic decisions about the management of citrus groves. The flowering of field-grown 'Valencia' sweet orange plants can be rapidly assessed by considering at least five plants and sampling canopy volumes of 0.5 m³ in at least one canopy position on each side of the plant row.O florescimento dos citros é um processo chave na citricultura e sua avaliação é dificultada devido à estrutura da copa e amostragem em campo. O objetivo desse artigo foi fornecer algumas indicações de como avaliar o florescimento de laranjeiras em condição de campo. Esse estudo foi conduzido em um pomar de laranjeiras 'Valência' [Citrus sinensis (L.) Osbeck] enxertadas em tangerineira 'Cleópatra' (Citrus reshni hort. ex Tanaka) ou limoeiro 'Cravo' (Citrus limonia Osbeck), com orientação Norte-Sul. As estruturas reprodutivas [botões florais, flores e frutos (diâmetro < 3 cm)] foram quantificadas semanalmente entre agosto e novembro de 2005, utilizando guias de 1 m² posicionadas no terço médio da copa das plantas, amostrando aproximadamente um volume de 1 m³. As guias foram divididas em duas partes para que duas pessoas pudessem realizar as avaliações, e posicionadas nas orientações sudeste, sudoeste, nordeste e noroeste, em sete plantas. Alguns aspectos do florescimento dos citros foram avaliados: (i) quantas plantas são necessárias para uma amostragem representativa do florescimento; (ii) em qual orientação deve ser feita a medida e (iii) qual volume da copa das plantas que deve ser amostrado. Ao se considerar os aspectos práticos da produção dos citros, um método rápido, simples e representativo é necessário para avaliar o florescimento, especialmente quando produtores têm que freqüentemente tomar decisões estratégicas no manejo dos pomares. O florescimento de laranjeiras 'Valência' em condição de campo pode ser rapidamente avaliado considerando-se pelo menos cinco plantas e amostrando-se volumes de copa de 0,5 m³ em pelo menos uma posição da copa em cada lado da linha de plantio

Comparação de ajustes dinâmicos de dificuldade aplicados a diferentes elementos de jogo

Trabalho de conclusão de curso (graduação)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Ciência da Computação, 2021.Conforme a indústria de videogames cresce, há o surgimento de novos cenários, sendo essencial manter os jogos divertidos para distintos perfis de consumidor, os quais podem possuir diversos níveis de habilidades e preferências. Nesse contexto é relevante a imple- mentação de um sistema de dificuldade adaptável ao jogador, assim oferecendo um desafio condizente ao jogador, evitando que o jogo se torne tedioso por estar muito fácil ou muito difícil. Diversos sistemas já foram modelados para lidar com essa questão, dentre eles alguns específicos ao gênero de jogo plataforma. No âmbito deste trabalho, objetiva-se comparar a eficiência de um sistema de ajuste dinâmico de dificuldade (ADD) por desem- penho aplicado a elementos diferentes de um jogo de plataforma. Foram comparados um total de quatro casos: sem aplicação de ADD, aplicação de ADD às plataformas, aplicação de ADD ao pulo e aplicação de ADD a ambos. Para tanto, utilizou-se uma evolução do trabalho de Rosa [1], sobre o qual foram implementadas as devidas modificações e para a condução de testes remotos cujo os dados foram coletados através de um Google Forms. A análise desses dados revelou conclusões multifacetadas, com o caso que melhor permite o estado de fluxo sendo o caso de ADD combinado, seguido pelo ADD de plataforma.As the video game industry grows, new scenarios are emerging, so it is essential to keep games fun for different consumer profiles, who may have varying levels of skills and pref- erences. In this context, it is relevant to implement a difficulty system that adapts to the player, thus offering a suitable challenge to the player, preventing the game from becoming tedious because it is too easy or too difficult. Several systems have already been modeled to deal with this issue, among them some specific to the platform game genre. In the scope of this work, the objective is to compare a system of dynamic difficulty adjustment (DDA) by performance applied to different elements of a platform game, to find out which one has the best efficiency in keeping the player in the flow state. A total of four cases were compared: without application of ADD, application of ADD to platforms, applica- tion of ADD to the jump and application of ADD to both. To this end, an evolution of the work of Rosa [1] was used, on which the necessary modifications were implemented and for conducting remote tests whose data were collected through a Google Forms. The analysis of these data revealed multifaceted conclusions, with the case that best allows the flow state being the case of combined ADD, followed by the platform ADD

As atividades científicas e a não neutralidade da ciência: o julgamento da geração espontânea

Este trabalho apresenta um breve estudo acerca das possíveis relações que permearam as atividades científicas de Louis Pasteur e Félix Pouchet no caso da geração espontânea, com foco nas questões que envolvem a não neutralidade da ciência. As reflexões que aqui são apresentadas baseiam-se nas premissas da construção social da ciência e numa visão externalista desta. Ambos auxiliaram para a análise de como funcionam as relações entre a não neutralidade da ciência, os mitos, as visões deformadas da ciência e o impacto destes nos indivíduos envolvidos em atividades científicas

Potential of maize (Zea mays L.) populations derived from commercial single-cross hybrids for extraction of partially inbred lines under different nitrogen availability

Extraction of inbred lines is a very important step in maize breeding since these lines will be used to obtain hybrids intended for the market. However, this expensive process, hinders genotype evaluation in contrasting environments, especially regarding nitrogen (N) content. This study aimed to evaluate the potential of maize populations for line extraction and select partially inbred lines under different soil nitrogen (N) availability. Five populations were evaluated regarding their potential for line extraction. Fifty-five S1 partially inbred lines were extracted from these populations. The top-cross method was used to evaluate lines by crossing them with two testers. Hybrids evaluation used 110 top-cross hybrids, five base populations, and six checks. Two trials were carried out in Dourados and Caarapó. One trial had adequate fertilization (high N) while the other was under stress condition (low N). Hybrid DKB 789 showed potential for extraction of partially inbred lines, aiming at selecting N use efficiency. Base population BP (07) was the most suitable for the extraction of partially inbred lines aiming at N use efficiency. Partially inbred lines BP (07) 13, BP (07) 14, and BP (07) 17 are the most suitable for the extraction of top-cross hybrids with high grain yield, efficiency, and responsiveness to N. Highlights Extraction of inbred lines is a very important step in maize breeding. Hybrid DKB 789 showed potential for extraction of partially inbred lines. BP (07) 13, BP (07) 14, and BP (07) 17 are the most suitable for the extraction of top-cross hybrids.Extraction of inbred lines is a very important step in maize breeding since these lines will be used to obtain hybrids intended for the market. However, this expensive process, hinders genotype evaluation in contrasting environments, especially regarding nitrogen (N) content. This study aimed to evaluate the potential of maize populations for line extraction and select partially inbred lines under different soil nitrogen (N) availability. Five populations were evaluated regarding their potential for line extraction. Fifty-five S1 partially inbred lines were extracted from these populations. The top-cross method was used to evaluate lines by crossing them with two testers. Hybrids evaluation used 110 top-cross hybrids, five base populations, and six checks. Two trials were carried out in Dourados and Caarapó. One trial had adequate fertilization (high N) while the other was under stress condition (low N). Hybrid DKB 789 showed potential for extraction of partially inbred lines, aiming at selecting N use efficiency. Base population BP (07) was the most suitable for the extraction of partially inbred lines aiming at N use efficiency. Partially inbred lines BP (07) 13, BP (07) 14, and BP (07) 17 are the most suitable for the extraction of top-cross hybrids with high grain yield, efficiency, and responsiveness to N. Highlights Extraction of inbred lines is a very important step in maize breeding. Hybrid DKB 789 showed potential for extraction of partially inbred lines. BP (07) 13, BP (07) 14, and BP (07) 17 are the most suitable for the extraction of top-cross hybrids

Nutritional status of schoolchildren according to school geographical localization in the city of Sorocaba, São Paulo, Brazil

OBJECTIVE: To estimate the prevalence of underweight, overweight and obesity in students of public schools from Sorocaba, São Paulo, Brazil. METHODS: This cross-sectional study enrolled 11,290 children aged seven to ten from public schools in the city of Sorocaba. Underweight, overweight and obesity were defined as, respectively, 85th and >95th body mass index percentiles for sex and age, according to the Centers for Disease Control and Prevention growth chart (CDC, 2000). The prevalence of nutritional alterations was assessed according to the geographical localization. RESULTS: Rates for underweight, overweight and obesity were respectively: Central area 3.4, 17.2 and 15.1%; Southern area, 4.2, 15.4 and 11.2%; Eastern area, 3.2, 14.7 and 12.7%; Northeast, 4.3, 11.9 and 10.7%; North, 5.8, 12 and 9.1%; Northwest 7.5, 11 and 9.1%; and Western regions 6, 11 and 9.2%. The differences between areas were significant (p85 e >95 do índice de massa corpórea por idade para sexo e idade propostos pelos Centers for Disease Control and Prevention (CDC, 2000). Comparou-se a prevalência de alterações nutricionais de acordo com a localização da escola. RESULTADOS: A prevalência de baixo peso, sobrepeso e obesidade nas crianças avaliadas, segundo a região geográfica de Sorocaba foi, respectivamente: Centro 3,4, 17,2 e 15,1%; Sul 4,2, 15,4 e 11,2%; Leste 3,2, 14,7 e 12,7%; Nordeste 4,3, 11,9 e 10,7%; Norte 5,8, 12 e 9,1%; Noroeste 7,5, 11 e 9,1%; Oeste 6,0, 11 e 9,2%. Os meninos apresentaram 5,3, 12,1 e 11,9% e as meninas 5,9, 12,3 e 8,2% de baixo peso, sobrepeso e obesidade, respectivamente. Houve diferença significativa na prevalência de alterações nutricionais entre as regiões da cidade (p<0,001) CONCLUSÕES: O Centro e o Leste de Sorocaba apresentaram as maiores taxas de escolares com excesso de peso, as regiões Noroeste e Oeste, as maiores taxas de baixo peso. Na análise por sexo, os meninos apresentaram maiores taxas de obesidade. Esses resultados podem ajudar a planejar políticas públicas para a prevenção da obesidade em escolares556

Projection spectrograph as a tool for light polarization classrooms demonstrations

This article describes the use of a projection spectrograph based on an overhead projector for use in classroom demonstrations on light polarization and optical activity. A simple adaptation on a previously developed apparatus allows illustrating several aspects of optical activity, such as circular and linear birefringence, including their wavelength dependence. Specifically, we use the projection spectrograph to demonstrate the optical activity of an aqueous solution of sugar (circular birefringence), of a quartz plate and of an overhead projector transparence film (linear birefringence). A historical survey about the optical activity discovery and the main principles involved is also presented

On an accidental degeneracy in the 31P{¹H} NMR chemical shifts in ruthenium diphosphine complexes

The [RuCl(bipy)(dppb)(4-pic)]PF6 complex was prepared and fully characterized. The X-ray crystal structure of this complex was determined in order to make an unambiguous distinction between the two possible positions of the 4-methylpyridine ligand (4-pic) in the compound: trans to phosphorus atom or trans to nitrogen atom. The [RuCl(bipy)(dppb)(4-pic)]PF6 complex exhibits an unusual temperature-dependent accidental degeneracy of the 31P chemical shifts in its solution NMR spectrum

Ensino de física inclusivo em nível universitário: o caso do Instituto de física da UERJ

This work is part of the research carried out as a conclusion of the full degree course in Physics at the State University of Rio de Janeiro (UERJ). This paper seeks to discuss the teaching of Physics at the university level in the current context of inclusive education for people with visual impairments. A questionnaire was developed that serves as a discussion tool on the inclusion of visually impaired students based on the answers given by the professors of a Physics Department. These teachers were asked about their training, their teaching practice and the teaching of Physics to students with visual impairment. Teacher training, or lack thereof, is problematic for the trulyinclusion of students with special needs at an educational level. Teachers are little prepared to deal with different student specificities. It was found that UERJ as an Institution only helps these students to access university education without showing any incentives for their permanence. The teachers are not supported by the UERJ so that their practice becomes really inclusive. Thus, school inclusion at the university level is not yet a reality within the Institute of Physics of this Institution.O presente trabalho faz parte de pesquisa realizada como conclusão do curso de licenciatura plena em Física da Universidade do Estado do Rio de Janeiro (UERJ). Este trabalho busca discutir o ensino de Física em nível universitário no atual contexto da educação inclusiva para pessoas com deficiência visual. Analisou-se um questionário que serviu de instrumento de discussão sobre a inclusão de alunos com deficiência visual a partir das respostas obtidas junto aos docentes de um Departamento de Física. Estes docentes foram questionados sobre sua formação, sua prática docente e o ensino de Física para alunos com deficiencia visual. A formação docente, ou a sua falta, mostra-se problemática para a efetiva inclusão de alunos público-alvo da educação especial em nível superior. Os docentes mostram-se pouco preparados para lidar com as diferentes especificidades de alunos. Foi verificado que a UERJ enquanto Instituição auxilia apenas ao acesso destes educandos ao ensino universitário sem mostrar incentivos a sua permanência. Os docentes não recebem nenhum tipo de apoio por parte da UERJ para que sua prática se torne realmente inclusiva. Assim, a efetiva inclusão escolar em nível universitário ainda não é uma realidade dentro do Instituto de Física desta Instituição

Seed germination and vigor of passion fruit hybrids

Most commercial plantations of passion fruit is propagate plants by seed, but germination is irregular, which hinders the growth of seedlings and uniformity, and is connected with the plant genotype. The objective of this study was to evaluate the germination and early growth of passion fruit hybrid seedlings, obtained from different genetic combinations. The hybrids were obtained from the cross between progenies from the breeding program of the Universidade Federal de Viçosa with hybrids of the Empresa Brasileira de Pesquisa Agropecuária and of the Viveiros Flora Brasil. The experimental design was completely randomized with six hybrids, five replicates and fifty seeds per experimental unit. Germination was assessed daily until the 28 days, and at the end of the period it was obtained the mean time germination, emergence speed index, seedling height, the length of shoots and roots, and the individual seedling dry matter (root + shoot)was assessed. Among the passion fruit hybrids evaluated, hybrid HB2 (UFVM0212 × BRS Sol do Cerrado) showed the highest germination and seedling biometric values and might be a genotype with potential for breeding programs for seed quality. The specific combining ability of parents can influence the quality of seeds and the vigor of passion fruit seedlings. A factor must be considered is the correct choice of maternal and paternal parents, since they influence the quality of seeds. Most commercial plantations of passion fruit is propagate plants by seed, but germination is irregular, which hinders the growth of seedlings and uniformity, and is connected with the plant genotype. The objective of this study was to evaluate the germination and early growth of passion fruit hybrid seedlings, obtained from different genetic combinations. The hybrids were obtained from the cross between progenies from the breeding program of the Universidade Federal de Viçosa with hybrids of the Empresa Brasileira de Pesquisa Agropecuária and of the Viveiros Flora Brasil. The experimental design was completely randomized with six hybrids, five replicates and fifty seeds per experimental unit. Germination was assessed daily until the 28 days, and at the end of the period it was obtained the mean time germination, emergence speed index, seedling height, the length of shoots and roots, and the individual seedling dry matter (root + shoot)was assessed. Among the passion fruit hybrids evaluated, hybrid HB2 (UFVM0212 × BRS Sol do Cerrado) showed the highest germination and seedling biometric values and might be a genotype with potential for breeding programs for seed quality. The specific combining ability of parents can influence the quality of seeds and the vigor of passion fruit seedlings. A factor must be considered is the correct choice of maternal and paternal parents, since they influence the quality of seeds